_ C .ap2020.collegeboard.org/Praott-aa857320- glucagon (a) A cell where PKB is always active has a mutation…

_ C .ap2020.collegeboard.org/Praott-aa857320- glucagon (a) A cell where PKB is always active has a mutation that results in the permanent activation of GSK3. Based on the information in Figure 2, predict the effect of this mutation on the activity of glycogen synthase. (b) Justify your prediction in part (a). Describe the process that results in the activation of multiple copies of PKB in response to the binding of a single molecule of insulin to its receptor. (d) Explain why insulin can stimulate the activation of PKB but not the activation of PK. () Explain why an increase in glycogen phosphorylase activity might result in an increase in O2 consumption in the cell. (1) A certain type of tumor results in the overproduction of glucagon. Researchers claim that treatment with insulin can counteract the effects of the excess glucagon on the pathway shown in Figure 2. Provide reasoning to justify the researchers’ claim. Time Left to Submit Work 0:17:34 Glycogen is a complex polymer of glucose molecules involved in the storage of energy in many organisms. Depending on the signals received by a cell, different enzymes are activated, which will lead to either the synthesis or breakdown of glycogen. The product of glycogen breakdown, glucose 1-phosphate, can be modified into glucose 6-phosphate, an intermediate of glycolysis (Figure 1). Glycogen Synthase YPE Glucose 6-Phosphate Glycogen Phosphorylase Glucose 1-Phosphate Glycogen ap2020.collegebo 1 In the liver, glycogen synthase and glycogen phosphorylase are regulated by kinases. These kinases transfer phosphate groups from ATP to amino acids in glycogen synthase and glycogen phosphorylase. Phosphorylase kinase B (PKB) is a kinase that regulates glycogen synthase kinase 3 (GSK3) activity. GSK3 regulates the activity of glycogen synthase. Phosphorylase kinase (PK) regulates the activity of glycogen phosphorylase. The activity of these kinases depends on the activation of signaling pathways in response to the binding of specific cell signals, including insulin and glucagon, to their receptors (Figure 2). Insulin Insulin Receptor Cell Membrane of a Liver Cell PKB GSK3 Glycogen Synthase Glucose Glucose Glycogen Time Left to Submit Work 00:16:16 Paste Response Insulin Insulin Receptor Cell Membrane of a Liver Cell PKB 1 GSK3 1 Glycogen Glucose Synthase 1-Phosphate Glycogen Glycogen Phosphorylase Glucose 6-Phosphate 1 Glycolysis _ Activates = Inhibits Glucagon Receptor Glucagon